Move --custom-launcher-page switch into app_list_switches.h.

ui/app_list/app_list_switches.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_APP_LIST_APP_LIST_SWITCHES_H_
 #define UI_APP_LIST_APP_LIST_SWITCHES_H_
 
 #include "ui/app_list/app_list_export.h"
 
 namespace app_list {
 namespace switches {
 
 // Please keep these flags sorted.
+APP_LIST_EXPORT extern const char kCustomLauncherPage[];
 APP_LIST_EXPORT extern const char kDisableAppInfo[];
 APP_LIST_EXPORT extern const char kDisableDriveAppsInAppList[];
 APP_LIST_EXPORT extern const char kDisableSyncAppList[];
 APP_LIST_EXPORT extern const char kEnableCenteredAppList[];
 APP_LIST_EXPORT extern const char kEnableExperimentalAppList[];
 APP_LIST_EXPORT extern const char kEnableHotwordAlwaysOn[];
 APP_LIST_EXPORT extern const char kEnableSyncAppList[];
 
 bool APP_LIST_EXPORT IsAppListSyncEnabled();
 
@@ skipping 10 matching lines @@
 // instead use AppListViewDelegate::ShouldCenterWindow. It checks a superset of
 // the conditions that trigger the position.
 bool APP_LIST_EXPORT IsCenteredAppListEnabled();
 
 bool APP_LIST_EXPORT IsDriveAppsInAppListEnabled();
 
 }  // namespace switches
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_APP_LIST_SWITCHES_H_